Reaction products of fatty acids, dialkanolamines, and alkenyl succinic acid anhydrides



Patented May 12, 1953 UNITE ill s'rArss ATENT OFFICE- REACTION PRODUCTSF FATTY ACIDS,

DIALKANOLAMINES, AND ALKENYL SUC- CINIC ACID ANHYDRIDES New York NoDrawing. Application December 30, 1M9, Serial No. 136,158

Claims.

This invention relates, broadly, to organic nitrogen compounds and tocorrosion-inhibiting compositions containing them. It is morespecifically concerned with the reaction products ob tained by reactingfatty acids, dialkanolamines, and alkenyl succinic acid anhydrides; andwith corrosion-inhibiting compositions comprising suitable vehiclescontaining these reaction products.

As is well known to those familiar with the art, Whenever machines anddevices have been constructed in whole or in part of metals,particularly of ferrous metals, the occurrence of surface corrosion haspresented serious problems. For example, farming implements arefrequently stored under conditions where they are subject to rusting.Rusting also presents problems in the storage of infrequently usedmachinery, in the shipment of machined metal parts, such as sewingmachine parts and gun barrels, and in the use of structural steelmembers, such as bridge trusses. These difficulties have been overcomein part by coating the exposed surfaces with paints, greases, oils, andthe like. In many cases,

however, it has been disadvantageous to use these expedients since it isoften necessary to remove such coatings completely before the object isused. Accordingly, recourse has been had to corrosion-inhibitingcompositions which can be applied to metal surfaces and which can beremoved easily and cheaply.

In the field of lubrication, the rusting of fer rous metal surfaces hasbeen a common occurrence. This has been a serious problem in steamturbines, particularly during the initial operation of newinstallations. The rusting is most pronounced at points where theclearance between bearing surfaces is very small, such as in thegovernor mechanism. This is usually caused by water entering the oilsupply, as by condensation, and becoming entrained in the oil throughoutthe circulating system, thereby coming into contact with the ferrousmetal surfaces. Manifestly, this constitutes a menace to the operationallife of the turbine.

Many materials have been proposed as coatins compositions or as additionagents for lubricating oils to inhibit rusting. In United States Letters Patents Nos. 2,124,628; 2,133,734; and

2,279,688. there were disclosed alkenyl succinic acids, and halogenatedand/or sulfurized derivatives thereof, as compounds useful in theprevention of corrosion. In these patents, the patentees stipulate thatthe acids must have at least 16 carbon atoms, and, preferably, 20 carbonatoms per molecule.

It has now been found that a new typ f corrosion inhibitor can beproduced from alkeny succinic acid anhydrides havin any number Of carbonatoms in the alkenyl radical thereof. It has now been discovered thatuseful corrosion illhibitors can be produced by first reactin a fattyacid with a dialkanolamine to p oduce an intermediate product, and thenreacting this intormediate product with an alkenyl succinic acidanhydride.

Accordingly, it is a broad object of th s inv ntion to provide novelcorrosion inhibitors. All? other object is to provide corrosioninhibitors produced from alkenyl succinic acids having any number ofcarbon atoms in the alkenyl radical. A specific object is to providecorrosion inhibitors by reacting a fatty acid with a dialkanolamine toproduce an intermediate product, and then reacting this intermediateproduct with an alrenyl succinic acid anhydride. A more specific objectis to provide substantially neutral vehicles containing such corrosioninhibitors. important object is to provide mineral lubricating oilscolitaining minor amounts of corrosion inhibitors of the type describedhereinbefore. Other objects and advantages of the present invention willbecome apparent to those skilled in the art from the following detaileddescription.

Broadly stated, the present invention provides new compositions ofmatter obtained by reacting a fatty acid containing at least about fivecarbon atoms per molecule with a dialkanolamine, in a molar proportionof about 1:1, respectively, to produce an intermediate product, andreacting an alkenyl sucoinic acid anhydride with the intermediateproduct, in a molar proportion varying between about 1:1, respectively,and about 2: 1 respectively. The present invention also provides asubstantially neutral vehicle containing between about 0.01 per cent andabout per cent, by weight, of these compositions of matter.

In general, the dialkanolamine reactants utilizable herein are thosecompounds having the structural formula,

wherein R and R are alkylene radicals or hydrocarbon-substitutedalkylene radicals, having between about two and about seven carbon atomsper radical. These radicals can be similar or dissimilar radicals.Ordinarily, they will be the same in any given molecule. Since it ismore diflicult to esterify secondary and tertiary alcohol groups, it ispreferable that the alkylene radicals do not contain secondary ortertiary carbon atoms attached to the hydroxyl group, so as to formsecondary and ztertiaryalcohol groups, respectively. However, because of"their greater commercial availability, it is preferred to usediethanolamine and hydrocarbon-substituted diethanolamines.

These compounds have the structural formula,

tween ammonia and a halogenated alcohol, such as 2-chlorobutanol-1. Thehalogenated alcohols, in turn, are produced by several methods, forexample, by careful halogenation of a dihydric alcohol.

Any fatty acid, or its anhydride or acid halide, can be reacted with thedialkanolamine reactant to'produce the intermediate products used inpreparing the reaction products of the present invention. Fatty acidscontaining substituent groups, such as halogen atoms, nitro groups,amino groups, etc., are also applicable herein. The fatty acid reactantscan be branched-chain or straightchain, and saturated or unsaturatedaliphatic monocarboxylic acids, and the acid halides and acid anhydridesthereof. Accordingly, when the term fattyacid is used herein, it must beclearly understood that the term embraces fatty acids, fatty'acidanhydrides, and fatty acid halides, and derivatives thereof.Particularly preferred are the fatty-acids having relatively long carbonchain lengths, such as a carbon chain length of between about 8 carbonatoms and about 30 carbon atoms.

Non-limiting examples of the fatty acid reactant are valeric acid;a-bromoisovaleric acid; hexanoic acid; hexanoyl chloride; caproic acidanhydride; sorbic acid; aminovaleric acid; amino hexanoic acid;heptanoic acid; heptanoic acid anhydride; 2-ethylhexanoic acid;a-bromo-octanoic acid;

decanoic acid; dodecanoic acid; undecylenic acid; tetradecanoic acid;myristoyl bromide;

erotic acid; selacholeic acid; heptacosanoic acid anhydride; montanicacid; melissic acid; keto- .triacontic acid; naphthenic acids; and acidsobtained from the oxidation of petroleum fractions.

The fatty acid reactant is reacted with the dialkanolamine reactant in amolar proportion of about 1:1. A molar excess of dialkanolaminereactant, as much as 25 mole per cent or more, can be usedadvantageously to ensure complete reaction. .After the reaction iscomplete, the excess, unreacted dialkanolamine reactant will be re moved.by usual means, such as by water washing or by distillation. However, asmall excess of dialkanolamine reactant in the intermediate has not beenfound deleterious to the purpose of producing an effective antirustagent therefrom. In any event, the net result will be. "an-interm d 4product produced by reacting the reactants in a 1:1 molar proportion.

The temperature at which the'reaction between the fatty acid reactantand the dialkanolamine reactant is effected is not too critical afactor. Since the reaction involved appears to be an amide-formationreaction, the general temperature conditions for that reaction, whichare well known to those skilled in the art, are applicable.

Nevertheless, it is usually preferred to operate at temperatures varyingbetween about C. and about C. It must be strictly understood, however,that the reaction between the fatty acid reactant and the dialkanolaminereactant can be effected at temperatures substantially lower than 130 C.and substantially higher than 160 0., and that this invention is not tobe limited to the preferred temperature range.

Water is formed as a by-product of the reaction between the fatty acidreactant and the dialkanolamine reactant. In order to facilitate theremoval of this water, to effect a more complete reaction in accordancewith the principle of le Chatelier, a hydrocarbon solvent which forms anazeotropic mixture with water can be added to the reaction mixture.Heating is continued with the liquid reaction mixture at thepreferredreaction temperature, until the removal of water by azeotropicdistillation has substantially ceased. In general, any hydrocarbonsolvent which forms an azeotropic mixture with water can be used. It ispreferred, however, to use an aromatic hydrocarbon solvent of thebenzene series. Nonlimiting examples of the preferred solvent arebenzene, toluene, and xylene. The amount of solvent used is a variableand non-critical factor. It is dependent on the size of the reactionvessel and the reaction temperature selected. Accordingly, a sufiicientamount of solvent must be used to support the azeotropic distillation,but a large excess must be avoided since the reaction temperature willbe lowered thereby. Water produced by the reaction can also be removedby operating under reduced pressure. When operating with a reactionvessel equipped with a reflux condenser provided with a water takeofftrap, sufficient reduced pressure can be achieved by applying a slightvacuum to the upper end of the condenser. The pressure is usuallyreduced to between about 50 millimeters and about 300 millimeters. Ifdesired, the water can be removed also by distillation, while operatingunder relatively high temperature conditions.

The time of reaction between the fatty acid reactant and thedialkanolamine reactant is dependent on the weight of the charge, thereaction temperature selected, and the means employed for removing thewater from the reaction mixture. In practice, the reaction is continueduntil the formation of water has substantially ceased. In general, thetime of reaction will vary between about six hours and about ten hours.

Without any intent of limiting the scope of the present invention, it ispostulated that the reaction between the fatty acid reactant and thedialkanolamine reactant results in the formation of a dialkanolamide ofthe fatty acid. Thus, the

reaction between valeric acid and the diethanolamine could proceed,theoretically, in accordance diethanolamine to form morpholine, orreactions could occur simultaneously between two molecules of the fattyacid and both the amino hydrogen and a hydroxyl group of thediethanolamine, as set forth in the following equations:

clmooon HmouLoH),

The reaction of Equation 3 would produce some unreacted diethanolarninein the reaction mixture, but this reaction probably does not occur to anappreciable extent. It will be apparent, however, that, in view of theforegoing, any designation assigned to these intermediate products,other than a definition comprising a recitation of the process ofproducing them, is not accurately descriptive of them.

Any alkenyl succinic acid anhydride or the corresponding acid isutilizable for the production of the reaction products of the presentinvention. The general structural formulae of these compounds are:

wherein R is an alkenyl radical. The alkenyl radical can bestraight-chain or branched-chain;

and it can be saturated at the point of unsaturation by the addition ofa substance which adds to olefinic double bonds, such as hydrogen,sulfur, bromine, chlorine, or iodine. It is obvious, of course, thatthere must be at least two carbon atoms in the alkenyl radical, butthere is no real upper limit to the number of carbon atoms therein. Inorder to produce the reaction products of this invention, however, anallienyl succinic acid anhydride or the corresponding acid must be used.Succinic acid anhydride and succinic acid are not utilizable herein. Forexample, the reaction product produced by reacting an intermediateproduct with snccinic acid anhydride is not an effective rust inhibitor.Although their use is less desirable, the alkenyl succinic acids alsoreact, in accordance with this invention, to produce satisfactoryreaction products. It has been found, however, that their usenecessitates the removal of water formed during the reaction, and also,often causes undesirable side reactions to occur to some extent.Nevertheless, the alkenyl succinic acid anhydrides and the alkenylsuccinic acids are interchangeable for the purposes of the presentinvention. Accordingly, when the term alkenyl succinic acid anhydride,is used herein, it must be clearly understood that it embraces thealkenyl succinic acids as well as their anhydrides, and the derivativesthereof in which the olefinic double bond has been saturated as setforth hereinbefore. Non-limiting examples of the alkenyl succinic acidanhydride reactant are ethenyl succinic acid anhydride; ethenyl succinicacid, ethyl succinic acid anhydride; propenyl succlnic acid hydride;sulfurized propenyl succinic acid anhydride; butenyl succinic acid;2-methylbutenyl succinic acid anhydride; 1,2-dichloropentyl succinicacid anhydride; hexenyl succinic acid anhydride; hexyl succinic acid;sulfurized 3-methy1 pentenyl succinic acid anhydride; 2,3-dimethylbutenyl succinic acid anhydride; 3,3- dimethylbutenyl succinicacid; 1,2-dibromo-2- ethyl-butyl succinic acid; heptenyl succinic acidanhydride; 1,2-diiodooctyl succinic acid; octenyl succinlc acidanhydride; octenyl succinic acid 2-methylheptenyl succinic acidanhydride; 4- ethylhexenyl succinic acid; diisobutenyl succinic acidanhydride; 2-isopropylpenteny1 succinic acid anhydride; nonenyl succinicacid anhydride; 2-propylhexenyl succinic acid anhydride; 'decenylsuccinic acid; decenyl succinic acid anhydride;5-methyl-2-isopropylhexenyl succinic acid anhydride;l,2-dibromo2ethyloctenyl succinic acid anhydride; decyl succinic acidanhydride; un decenyl succinic acid anhydride; 1,2-dichloroundecylsuccinic acid; 3-ethyl-2-t-butylpentenyl succinic acid anhydride;triisobutenyl succinic acid anhydride; dodecenyl succinic acidanhydride; dcdecenyl succinic acid; 2-propylnoneyl succinic acidanhydride; 3butyloctenyl succinic acid anhydride; tridecenyl succinicacid anhydride; tetradecenyl succinic acid anhydride; hexadecenylsuccinic acid anhydride; sulfurized octadecenyl succinic acid; octadecylsuccinic acid anhydride; 1,2 dibromo 2 methylpentadecenyl succinic acidanhydride; 8 propylpentadecyl succinic acid anhydride; eicosenylsuccinic acid anhydride; l,2-dichloro-2-methylnonadecenyl succinic acidanhydride; 2-octyldodecenyl succinic acid; 1,2-diiodotetracosenylsuccinic acid anhydride; hexacosenyl succinic acid; hexacosenyl succinicacid anhydride; and hentriacontenyl succinic acid anhydride.

The methods of preparing the alkenyl succinic acid anhydrides are wellknown to those familiar with the art. The most feasible method is by thereaction of an olefin with maleic acid anhydride. Since relatively pureolefins are difficult to obtain, and when thus obtainable, are often tooexpensive for commercial use, alkenyl succinic acid anhydrides areusually prepared as mixtures by reacting mixtures of olefins with maleicacid anhydride. Such mixtures, as well as relatively pure anhydrides,are utilizable herein.

The alkenyl succinic acid anhydride reactant is reacted with theintermediate product in a proportion varying between about one inole andabout two moles of alkenyl succinic acid anhydride reactant for eachmole of dialkanolamine reactant used in the preparation of theintermediate product.

The reaction between the alkenyl succinic acid anhydride reactant andthe intermediate product takes place at any temperature ranging fromambient temperatures and upwards. This reaction is apparently amonoester formation reaction eifected by the well known addition of theanhydride group to an alcohol group. This addition proceeds at anytemperature, but tempera tures of about 1l5-130 C. are preferred. Whenan alkenyl succinic acid is used, water is formed. Therefore, in thiscase, the reaction temperature, preferably, should be somewhat higher.

The reaction between the alkenyl succinic acid anhydride reactant andthe intermediate product proceeds smoothly in the absence of solvents,at

tural formulae:

atmospheric pressure. However, the occurrence of undesirable sidereactions is minimized when a solvent is employed. Since a small amountof water is usually formed also when an alkenyl succinic acid anhydrideis used in the reaction, the solvent employed is preferably one whichwill form an azeotropic mixture with water. These solvents have beendiscussed fully, hereinbefore, in conjunction with the reaction betweenthe fatty acid reactant and the dialkanolamine reactant. The samesolvents and the same methods of using them are applicable to thereaction between the intermediate product and the alkenyl succinic acidanhydride reactant. For example; products of this invention have beenprepared at temperatures varying between about 115 C. and about 130 C.,using an aromatic hydrocarbon solvent of the benzene series.

The time of reaction is dependent on the size of the charge, thereaction temperature selected, and the means employed for removing anywater from the reaction mixture. Ordinarily, the addition reaction ofthe anhydride reactant is substantially complete within a few minutes.In order to ensure complete reaction, however, it is preferred tocontinue heating for several hours. When water is formed during thereaction, as when an alkenyl succinic acid is used, the completion ofthe reaction is indicated by a substantial decrease in the formation ofwater. In general, the reaction time will vary between several minutesand about ten hours.

Without any intent of limiting the scope of the present invention, it ispostulated that the reaction products contemplated herein are esteramideproducts of the dialkanolamine reactant having at least one freecarboxylic acid group. For example, when the theoretical intermediateproduct of Equation 1 is reacted with two moles of decenyl succinic acidanhydride the reaction product can contain any, or several, products,such as those set forth in the following struc- HO O C-C (H)C10Hn CiHiOOC-CHa C4HBCON C21140 C--CH2 HO O C- (H)C1oHn CioHm CIHO O C CHnHC O OCzHA N0 CCAHO H2O C 0 0 (321514 H C O OH (.ImHw

C4HOCON CaHqOH CwHm CQHAOOCCHiHOOOCZH NOCC4H0 H2GCOOC2H4 HOOC H H COOHCioHn H V CAHICON CzH4OOCCH2 one mole of diethanolamine to produce anintermediate product, which is then reacted with two moles of decenylsuccinic acid anhydride may be defined as valericacid-{-diethanolamine+deceny1 succinic acid anhydride (121:2).

In addition to the products described in the illustrative examples, setforth hereinafter, nonlimiting examples of the reaction productscontemplated herein are those produced by reacting the followingcombinations of reactants: valeric aoid+diethanolamine+ethenyl succinicacid anhydride (121:2); a-bromoisovaleric acid+dipropanolamine+ethylsuccinic acid (121:1.8); hexanoic acid+di-iso-propanolamine+propenylsuccinic acid anhydride (1:1:1) hexanoyl chloride+2,2-iminobutanol1+sulfurized propenyl succinic acid anhydride (1:122); caproic acidanhydride+3,3 -iminodibutanol- 1 +butenyl succinic acid (1:224) sorbicacid+4,4'-iminodibutanol-l+1,2-dichloropentyl succinic acid anhydride(12121.5); aminovaleric acid+di-tert-butanolamine+hexenyl succinic acid(12122), aminohexanoic acid+3,3' iminodipentanol- 2 +sulfurized3-methylpentenyl succinic acid anhydride (1 2 1 2 1.2) heptanoicacid+6,6-iminodihexanol- 1+2,3-dimethylbutenyl succinic acid anhydride(121:2) heptanoic acid anhydride+7,7-iminodiheptano1-1+1,2-dibromo 2ethylbutyl succinic acid (122:2); 2-ethylhexanoicacid+diethano1amine-i-heptenyl succinic acid anhydride (1 2 1 2 1.7)a-bromooctanoic acid+dipropanolamine-l-1,2-diiodooctyl succinic acid(121:1); decanoic acid-{- di-iso-propanolamine+octenyl succinic acidanhydride (121z2) dodecanoic acid+2,2-iminodibutanol-l+2-methylheptenylsuccinic acid anhydride (12121); undecylenicacid+3,3'-iminodibutanol-l+4-ethylhexenyl succinic acid (12122)tetradecanoic acid+b,4'-iminodibutanol 1+diisobutenyl succinic acidanhydride (121:2); myristoyl bromide+di tertbutanolamine+2-propylhexenyl succinic acid anhydride (121:1)hexadecanoic acid+3,3-iminodipentanol-2+decenyl succinic acid (1:121.6);palmitic acid+6,6'-iminohexanol-1+decenyl succinic acid anhydride(1:122) oleic acid-P1,!-iminodiheptanol-1+undecenyl succinic acidanhydride (12121.4); heptadecanoicacid+diethanolamine+1,2-dichl-oroundecyl succinic acid (121:2) stearicacid-dipropanolamine+dodeceny1 succinic acid (1:1:1.8); linoleic acid+diiso propanolamine+2-propylnonenyl succinic acid anhydride (12121);xylylstearic acid+2,2'-iminodibutanol-1+triisobutenyl succinic acidanhydride (12122); a-dodecyl tetradecanoic-acid+3,3-iminodibutanol-1+hentriacontenyl succinic acid anhydride(1:121); arachidic acid+4,4'-iminodibutanol-1+hexacosenyl succinic acidanhydride (1:122); behenic acid+di-tert-butanolamine+hexacosenylsuccinic a-cid (1:121.2); behenolicacid+3,3-iminodipentanol-2+1,2-diiodotetracosenyl succinic acidanhydride (1:1:2); erucic acid+6,6-iminodihexanol-l+2-octyldodecenylsuccinic acid anhydride (121:1.4); erucic acid anhydride+7,7-iminodiheptanol-l (1 2 2 2 2.8) cerotic acid+diethanolamine+eicosenylsuccinic acid anhydride (1:122) selacholeic acid+dipropanolamine+1,2-dibromo-2-methylpentadecenyl succinic acid anhydride (1:1:1)heptacosanoic acid anhydride+ di iso propanolamine+octadecyl succinicacid anhydride (12224) montanic acid+2,2-iminodibutanol-l (121:1);melissic acid-i-di-tert-b-utanolamine+sulfurized octadecenyl succinicacid anhydride (121:2) and ketotriacontic acid+7,7- iminodiheptanol-1+hexadecenyl succinic acid anhydride (121:2).

The following specific examples are for the purpose of illustrating thepresent invention, and of demonstrating the advantages thereof. It mustbe strictly understood that this invention is not to be limited to theparticular reactants and molar proportions employed, or to theoperations manipulations described therein. A wide variety of otherreactants and molar proportions, as set forth hereinbefore, may be used,as those skilled in the art will readily understood.

The alkenyl succinic acid anhydrides used in the following specificexamples are commercial mixtures of alkenyl succinic acid anhydrides inwhich the number of carbon atoms in the alkenyl radical varies betweenspecified limits. The Cli-sASAA is a mixture of hexeny-l, hep-tenyl, andoctenyi succinic acid anhydrides; Cs-mASAA is a mixture of octenyl,noneyl, and decenyl succinic acid anhydrides; and CIO-IZASAA is amixture of decenyl, undecenyl, dodecenyl succinic acid anhydrides.

PREPARATION OF INTERMEDIATE PRODUCTS Example 1 Stearic acid (1 mole)(284 grams) and diethanolamine (1 mole) (105 grams) were weighed into areaction vessel prev'ided with a mechanical stir rer, a thermometer, anda condenser device (reflux take-oh) for removing water from the reactionmixture as it is evolved in an azeotropic mixture of water and xylene.The reactants were heated to 150 G. Then, the reflux take-cit was filledwith xylene, and 100 milliliters of xylene were gradually added to thereaction mixture. The initial xylene refluxing occurred at a 155 C. .pottemperature. .A-f-ter 3.25 hours, the pot temperature which sustained axylene reflux was 163 'C. The amount of water collected from thereaction was 23AM mill-iters (theory is 18 milliliters for amidedomination). Xylene was removed under reduced pressure, withthe-reactants at 100 C. The residue thus obtained, was a wax-like,tan-colored solid having a neutralization number of fill-5.

Example 2 Oleic acid ("1 mole) (.232 grams) and dietharro-lamine (12moles) (125 grams) were weighed into a, reaction vessel provided withalmechanical stirrer, a thermometer, and a. reflux :tahe-ofi. The refluxtaxes-oh was filled xylene, and xylene (.200rmilli1iters) was added tothe reaction vessel. The reaction mixture was lieazted to 145 (3.,whereupon refluxing commenced. .Refluxing 75 ml. water-{ 20 m1. t-butylalcohol '75 ml. water+50 m1. t butyl alcohol '25 water+20 ml. t-hutylalcohol 100ml. water-l-no ml. t-butylalcohol qihehbutyl alcohol was usedto provide a more eificient separation of the aqueous and the organiclayers. The diethanolamine-free xylene solution of intermediate productwas filtered and the xylene was removed at a. pot temperature of C.,under reduced pressure. The liquid intermediate product had aneutralization number of 1.3.

Example 3 Stearic acid (0.344 mole) (95 grams) and diethanolamine (0.419mole) (44 grams) were wei hed into a reaction vessel equipped with amechanical stirrer, a thermometer, and a reflux take-oh". The reactantswere heated to 120 C. Then, the reflux take-01f was filled with xylene,and xylene milliliters) was added to the reaction mixture. Refluxing wasmaintained, for 4.75 hours, at a pot temperature of 140-15? C. A totalof 8.7 milliliters of water was collected. The reaction mixture wascooled to 95 C. and washed four times with the following distilled watermixtures:

('1) 50 ml. water+20 m1. t-butyl alcohol (2) 75 ml. water (3) 50 ml.water (4) 50 ml. water The diethanolamine-free xylene solution ofintermediate product was filtered, and topped free of xylene underreduced pressure, at a pot temperature'of 100 C. The wax-like,tan-colored, solid product has a neutralization number of 0.9.

Example 4 An intermediate reaction product was produced, in (the mannerdescribed in Example 1, using valeric acid and diethanolamme in a molarProportion of 1:1, respectively.

Example 5 An intermediate reaction product was produced, in the mannerdescribed in Example 2, using caprylic acid and diethanolamine, in amolar proportion of 1:1.2, respectively.

Example 6 An intermediate product was prepared, in the manner describedin Example 1, using dodecanoic acid and diethanolamine, in a molarproportion of 1:1, respectively.

Example 7 Anintermediatereaction product was prepared in the mannerdescribed in Example 1, using oleic acid and -di-isopropanolamine, in amolar proportion of 1:1, respectively.

PREPARATION OF THE FINAL REACTION PRODUCT .Example 8 .A portion, 37.1grams (0.1 mole) of the intermediate productdescribed in Example 1, and59 grams (0.2 mole) of C1o-12ASAA were placed in a reaction vesselprovided with a mechanical stirrer, a thermometer, and a refluxtake-01f. The reaction -mixture was heated atl15-l20 C. 'for0l5 hour.Then, the reflux take-ofi was filled with benzene, and benzene (30milliliters) was added to the reaction mixture. Refluxing was maintainedfor one 'hour, with the flask contents at C. No water was collected. Theflask contents were diluted with additional 70 milliliters of benzene.The resultant solution was filtered and benzene was removed byevaporation 11 on the steam bath. The liquid reaction product had aneutralization number of 129.

Example 9 tion was stopped and the benzene was removed under reducedpressure. The liquid reaction product had a neutralization number of 48.

Example 10 A portion, 36.9 grams (0.1 mole) of the intermediate productdescribed in Example 2 and 44.4 grams (0.15 mole) of C1o-r2ASAA wereplaced in a reaction vessel and heated at 115-125 C., for two hours. Nosolvent was used. The liquid reaction product had a neutralizationnumber of 109. Example 11 A portion, 37.1 grams (0.1 mole) of theintermediate product described in Example 3 and 41.9 grams (0.2 mole) ofCs-aASAA were heated together at 120-125 C. for 2.75 hours. The liquidreaction product had a neutralization number of 158.

. Example 12 Ca-mASAA and the intermediate product described in Example3 were reacted in a molar proportion of 2:1, respectively, at 125130 C.for 1.5 hours, using the procedure of Example 10. The reaction producthad a neutralization number of 145. Example 13 C1o-12ASAA and theintermediate product described in Example 3 were reacted in a molarproportion of 1.411, respectively, at 115-118 C. for 2.5 hours, usingthe procedure of Example 10.

The reaction product had a neutralization number of 95.

- Example 14 ClO-IZASAA. and the intermediate product described inExample 3 were reacted in a molar proportion of 1.6:1, respectively, at115-118 C., for 2.5 hours, using the procedure of Example 10. Thereaction product had a neutralization number of 112.

Example 15 C10-12ASAA and the intermediate product described in Example3 were reacted in a molar proportion of 1.8:1, respectively, at 110-120C., for 2.5 hours, using the procedure of Example 10. The reactionproduct had a neutralization number of 123.

Example 16 Example 17 C1o-12ASAA and the intermediate product describedin Example 2 were reacted, in a molar 12 proportion of 2:1,respectively, at 124 C., for two hours, using the procedure of Example10. The reaction product had a neutralization number of 131.

Example 18 Cio-12ASAA and the intermediate product described in Example2 were reacted in a molar proportion of 1.9:1, respectively, at 120-132C., for 2.25 hours, using the procedure of Example 10. The reactionproduct had a neutralization number of 123.

Example 19 C'1o-12ASAA and the intermediate product described inExample" 4 were reacted in a molar proportion of 2: 1, respectively, at123-125 C., for 1.75 hours, using the procedure of Example 10. Thereaction product had a neutralization number of 159. I

Example 20 C10-12ASAA and the intermediate product described in Example5 were reacted in a molar proportion of 2:1, respectively, at 120-130C., for 1.5 hours, using the procedure of Example 10. The reactionproduct had a neutralization number of 166.

Example 21 ClO-IZASAA and the intermediate product described in Example6 were reacted in a molar proportion of 2:1, respectively, at 122 C.,for two hours, using the procedure of Example 10. The reaction producthad a neutralization number of 141.

Example 22 C1o-12ASAA and the intermediate product described in Example7 were reacted in a molar proportion of 2:1, respectively, at 120-125C., for 1.5 hours, using the procedure of Example 10. The reactionproduct had a neutralization number of 130.

Example 23 A reaction product was prepared by reacting succinic acidanhydride and the intermediate product described in Example 2, in amolar proportion of 2:1, respectively, at 115-119" C., for two hours,using a toluene reflux in the manner described in Example 8. Thereaction product had a neutralization number of 152.

In order to demonstrate the outstanding properties of the reactionproducts of this invention, typical rust test data and emulsion testdata were obtained for mineral lubricating oil blends containing thereaction products described in the examples. Table I.

The mineral oil used in these tests was a blend of solvent-refined,Midcontinent residual stock with a solvent-refined, Midcontinent(Rodessa) distillate stock. It had a specific gravity of 0.872, a fiashpoint of 445 F., and a Saybolt Universal viscosity of 407.7 seconds atF. This mineral lubricating oil is suitable for use in steam turbines.Unless otherwise indicated in the tables, the test oils contained 0.2per cent by weight of 2,6-di-t-butyl-4-methyl phenol and 0.1 per cent byweight of phenyl-a-naphthylamine, both well known anti-oxidants.

The test method used to distinguish the rusting characteristics oflubricating oil blends was the ASTM test D665-44T for determining RustPreventingCharacteristics of Steam Turbine Oils in Presence of Water, inwhich synthetic sea water was used as well as distilled water. The

Pertinent test data are set forth in synthetic sea water contained 2.5 fchloride, 11 grams of magnesium chloride hexa hydrate, 4 grams of sodiumsulfate, and 1.2 grams of calcium chloride per liter. in this test ardrioal polished steel specimen is suspended and soaked in 30.0 cubiccentimeters of the .oil under test at 140 F. for thirty minutes. cubiccentimeters of synthetic sea water (or distilled water) are added andthe mixture is stirred at 1000 R. P. M. After 48 hours, the steelspecimen is removed and examined for evidence of rust on the portion ofthe specimen which hangs in the oil. In the tables, rust test resultsare given in terms of per cent of exposed metal surface which hasrusted. The complete rusting which is evident when uninhibited base oilsare tested is taken as 100 per cent.

The emulsion test used is the emulsion test for lubricating oils,Federal stock Catalog, sec- IV, quart 5, Federal SpecificationsTELL-791b,, February 19, 1942. in test method 320. 13., 40 cubiccentimeters of oil and 40 cubic centimeters of emulsant in a 100-cubiccentimeter graduated cylinder are stirred with a paddle at 1500 P. for 5minutes, at 130 F. Separation of the emulsion is observed while thecylinder is kept at 130 F. The figures in the tables show the number ofminutes at which there is no .continuous layer of emulsion between theoil and the emulsant, or the number of cubic centimeters of emulsionpersisting at the .end of thirty minutes.

sirable emulsion characteristics to the oil. Some of these reactionproducts have poorer emulsion characteristics others. Accordingly, atsome concentration the emulsion characteristics of the blend may not hedesirabl In such an event, however, a demulsifyin a ent, of whichseveral are well known :to the art, can be incorporated in the blend toimproue the emulsion characteristics thereof. lit must be noted that theintermediate product of Example 2 was entirely incfieotiiae inpreventing rusting in the presence .of sea water and that it was veryunsatisfactory in the presence of distilled water. Likewise, thereaction product made with sue-.- cinic acid .anhydride (Example 23) wasnot satisfactory, demonstrating the necessity of the alkenyl group inthe succinic acid anhydride molecule.

Erample 24 The rusting characteristics of amineral luhr eating oilcontainin the product of E amine 8 were rfurther tested, along with theoxid tion characteristics thereof, :hll means hi" the Test Method13943-95517. In accordance awith this test, the oil and distilled waterare placed in a large test tube, which is .maintamed a 20. F- A polishedcopper-iron catalyst coil :is inserted into the oil, but it does notextend into the water layer. Oxygen gas is .passed through the water andoil at the rate of :three liters per hour throughout the QOOO-hour testperiod. The test TABLE !R ust: Test, Ben. Reactants cent Metal g-3 1 22?Prod of Proportion Percent Rusted 1 ASAA/Inter- Cone.

e mediate in 011 S D D 1 so. ,ist. ist. 1 Fatty Acld Amme Water Water:Water N501 (UninhibitedOil)-.. -i 9 Oleic Diethanolamine Clo-12 1:,1 10do ..-.do "Cum: 1.5:1 04-05 0.03 '18.. d0 do 1. 010-12 14921 0.05 '0. 0217 .110 d0 010-12 221 0.05 0. 03 0. 02 8 r. Stearlc d0 .010-12 .221 0.05

0.03 0. 02 0.01 11 i d0 do Co-x 221 0.07 0. 02 .12 d0 ..d0 .i Cs-Pm. 2:10.05 0. 02 0.91 13" .do d0 Clo-12 1.411 0.05 0. 03 14 do .110 C10121:5:1 0.05 0.03 1. 8:1 0. 05 1.921 0.05 2:1 01 05 O. 01 .201 Caprylic do(210m .221 0:05 21 Dodecanoic do C o-12 2:1 (22 OleicDiisopropanolamiue... 010-12 '2:1 0.075 2 d0 Diethanolamine None... 0.2523 do do Suceiuic... 2:1 0.05

ASA'A is alkenyl suceinic acid anhydride.

From the .data set forth in the tables, .it will be apparent that goodantirust characteristics are imparted to lubricating oils which containthe reaction products of the ,present invention. To be completelyacceptable for use in a turbine oil, an additive, preferably, should notimpart undesirable emulsion "characteristics thereto. It will beapparent from "the emulsion *test data given in the table thatpa'sa-classy'the *reaction ,oil .uefined hereinbefor containing .hv weight0.05 per oentof the prpduct qf Example 18,112 cent assent-bowl-4=methohenot and ll-. per .cent .phenyl-a-nanh hylam ne was not r s dized inthis test as evidenc d bran -N- .Q .0.04. The catalyst coilshowed onlya'fewsp ots of rust at the top ,thereof. -When"the il'is'tested withoutthe -a'ntirust additive the catalyst coil -rusts withinasshort aperiodoftime as twenty- *pro'cluctscf this inventiondo not impart unde-7 *four hours.

. pOSeS.

, Example I PREvENTfoN OF ATMOSPHERIC CORROSION In order to evaluate thenew reaction products as coatingcompounds for the prevention ofatmospheric corrosion, a test was run as follows: Two polished steelspecimens were coated with the reaction product of Example 11 by dippingthem in a two per cent by weight solution of the product in benzene.Likewise, two additional specimens were coated with the reaction productof Example 19, and two more were coated with the reaction product ofExample 18. Two other specimens were. left uncoated, as the controls.These-specimens were suspended in the chemical laboratory, exposed tothe various vapors and fumes ordinarily found therein. After 24 hours ofsuch exposure, none of the specimens showed visible signs of corrosion.Then, each specimen was immersed in distilled water for about seconds,by raising a separate beaker of distilled water under each one. Afterone hour this procedure was repeated. The control specimens showed alight surface rusting about five minutes after this treatment. Thecoated specimens remained free of corrosion. The immersion process wasrepeated (considering initial immersion time as zero) at 20, 22, 24, 26,42, 44, 46, 48, and 50 hours. Considerable more rusting'was noted on thecontrol specimens after each immersion, but, the coated specimens werestill free of any trace of corrosion.

In the foregoing specific illustrative examples, the effectiveness ofthe reaction products for the prevention of rust in lubricated systemsand for the prevention of atmospheric corrosion has been demonstrated.In addition to the use in turbine oils or as coating agents, thesereaction products are utilizable for numerous pur- They can be added toa wide variety of vehicles to produce improved compositions. They can bedissolved in the vehicle or they can be dispersed therein, in the formof suspension or emulsions.

The vehicles can be liquids or plastics, the basic requirement beingthat they must be spreadable over metal surfaces. Spreading may beaccomplished by immersion, flooding, spraying, brushing, trowelling,etc. Additionally, the vehicle should be substantially neutral. It canbe oleaginous, i. e., substantially insoluble in water, or it can beaqueous. Aqueous vehicles include aqueous solutions of liquids, such asalcohol-water mixtures and the like. Oleaginous vehicles can behydrocarbon materials, such as mineral oils and hydrocarbon solvents, ornonhydrocarbon materials, such as fatty oils and fats.

Non-limiting examples of suitable vehicles for the additives of thisinvention are mineral lubricating oils of all grades; gasolines andother light petroleum products, such as fuel oil; water, alcohols, suchas ethanol isopropanol, butanol, cyclohexanol, methylcyclohexanol,octanol, decanol, dodecanol, hexadecanol, octadecanol, oleyl alcohol,benzyl .alcohol, etc.; phenols; glycols, such as ethylene glycol,propylene glycol, butylene glycol, glycerol, etc.; ketones, such asacetone, methyl ethyl ketone, dipropyl ketone, cyclohexanone, etc.; ketoalcohols, such as benzoin; ethers, such as diethyl ether, dipropylether, diethylene dioxide, dichloro diethyl ether,

diphenyl oxide, diethylene glycol, triethylene glycol, ethylene glycolmonobutyl ether, etc.;

neutral esters, such as ethyl acetate, butyl propionate, cresyl acetate,dodecyl acetate, ethyl maleate, butyl stearate, tridecyl phosphate,tributyl trithiophosphate, triamyl phosphite, etc.; petroleum waxes,such as slack wax and paraflin wax; natural waxes, such as carnauba wax,Japan wax, beeswax, etc.; natural fats and oils, such as sperm oil,tallow, cottonseed oil, castor oil, linseed oil, tung oil, soybean oil,oiticica oil, tar oil, oleo oil, etc.; hydrocarbons and. halogenatedhydrocarbons, such as butanes, chlorinated hexanes, octanes, brominateddecanes, dodecanes, Freon, eicosane, benzene, toluene, xylenes, cumene,indene, alkyl naphthalenes, etc.; greases; asphalts; chlorinatedpetroleum fractions, such as chlorowax; and paints, varnishes and thelike.

As those skilled in the art Will readily appreciate, the applications ofthe compositions of the present invention are many. Lubricating oils ofall types usually permit corrosion of metal surfaces. This poses aproblem in the lubrication of all types of engines, particularly steamturbines. Lubricating oils containing the reaction products of thisinvention are efiectively inhibited against such corrosion. Diesel fuelscontaining these additives will have less tendency to corrode injectionnozzles. Steam cylinder oils and cutting oils can be inhibited againstcorrosive tendencies by the addition thereto of these new additives,particularly the more emulsive types. Greases can be inhibited likewise.Additionally, the more emulsive products of this invention can besubstituted in whole or in part, for the emulsifying agents commonlyused in compounding greases, cutting oils, steam cylinder oils, etc.Hydraulic systems can be protected against corrosion by using hydraulicfluids containing the additives of the present invention.

The storage of infrequently used machinery, and the shipment and storageof metal shapes and metal parts, such as machined sewing machine partsor gun parts, present corrosion problems. Such corrosion can beprevented by treating them with slushing oils containing the additivesof this invention, by coating them with organic solvent solutions ordispersions of these additives, such as the benzene solutions describedhereinbefore, or by treating the surfaces thereof with dispersions ofthese additives in water. Corrosive tendencies of coolants andantifreeze solutions or mixtures, such as those used as coolants ininternal combustion engines, can be reduced by addition thereto of thereaction products of this invention. Such antifreezes include water,alcohol-water, glycols, glycol-water, etc. When gasoline and other fuelsare stored in drums or tanks, water often enters the storage space, asby breathing, and corrodes the inner surfaces thereof. This can beprevented through the use of the additives contemplated herein.

Relatively more permanent corrosion-preventive coatings can be producedby the application to metal surfaces of paints, and the like, containingthe additives of this invention. Vehicles utilizable for this purposeare paints, varnishes, lacquers, drying oils, asphalt roofingcompositions, and the like."

The amount of the reaction products which are added to a vehicle toproduce a composition in accordance with this invention varies betweenabout 0.01 per cent and about 50 per cent by weight,v depending on thespecific use contemplated and on the specific reaction product selected.Generally, itis suificient to use an 1? amount varying between about0.01 per cent and about per cent. However, smaller amounts, as low asabout 0.005 per cent will be effective in some cases. Likewise, amountsup to as much as about 50 per cent are required when the vehiclecontains resinous bodies, or when the reaction product is also used anan emulsifier, such as in a steam cylinder oil.

Other substances in addition to the reaction products of this inventioncan be added to the compositions contemplated herein to impart otherdesirable properties thereto. For example, there may be addedantioxidants, pour point depressants, V. I. improvers, antidetonants,octane number improvers, emulsifiers, thinners, driers, etc.

Although the present invention has been described with preferredembodiments, it is to be understood that modifications may be resortedto without departing from the spirit and scope thereof, as those skilledin the art will readily understand. Such variations and modificationsare considered to be within the purview and scope of the appendedclaims.

What is claimed is:

1. A corrosion-inhibiting composition which comprises a substantiallyneutral vehicle containing between about 0.01 per cent and about 50 percent, by weight, of the final reaction product obtained by initiallyreacting a fatty acid containing at least about five carbon atoms permolecule with a dialkanolamine having between two and seven carbon atomsper alkanol radical, in a molar proportion of about 1:1, respectively,at a temperature of between about 130 C. and about 160 C. to produce anintermediate product, and then reacting an alkenyl succinic acidanhydride with said intermediate product. in a molar proportion varyingbetween about 1:1, respectively,

and about 2:1, respectively, at a temperature of between about 110 C.and about 130 C.

2. The composition of claim 1, wherein said vehicle is an oleaginousvehicle.

3. The composition of claim 1, wherein vehicle is an aqueous vehicle.

4. The composition of claim 1, wherein vehicle is a non-hydrocarbonvehicle.

5. The composition of claim 1, wherein vehicle is a fatty oil vehicle.

6. The composition of claim 1, wherein vehicle is a hydrocarbon vehicle.

'7. The composition of claim 1. wherein said fatty acid contains betweenabout 8 and about carbon atoms per molecule.

8. The composition of claim 7, wherein said dialkanolamine is a compoundhaving the formula, HN CH2CHROH 2, wherein R is selected from the groupconsisting of hydrogen atoms and alkyl radicals.

9. The composition of claim 8, wherein said vehicle is a minerallubricating oil.

10. A mineral lubricating oil containing between about 0.01 per cent andabout per cent, by weight. of the final reaction product obtained byinitially reacting stearic acid with diethanolamine, in a molarproportion of about 111, respectively at a temperature of between about130 C. and about 160 C. to produce an intermediate product, and thenreacting an alkenyl sucoinic acid anhydride, having between about tenand about twelve carbon atoms per alkenyl radical, with saidintermediate product. in a molar proportion of about 2:1, respectively,at a temperature of between about 110 C. and about 130 C.

11. A mineral lubricating oil containing besaid said

said

said

tween about 0.01 per cent and about 50 per cent. by weight, of the finalreaction product obtained by initially reacting stearic acid withdiethanolamine, in a molar proportion of about 1:1, respectively, at atemperature of between about 130 C. and about 160 C. to produce anintermediate product, and then reacting an alkenyl succinic acidanhydride, having between about eight and about ten carbon atoms peralkenyl radical, with said intermediate product, in a molar proportionof about 2:1, respectively, at a temperature of between about C. andabout C.

12. A mineral lubricating oil containing between about 0.01 per cent andabout 50 per cent, by weight, of the final reaction product obtained byinitially reacting oleic acid with diethanolamine, in a molar proportionof about 1:1, respectively, at a temperature of between about 130 C. andabout C. to produce an intermediate product, and then reacting analkenyl succinic acid anhydride, having between about ten and abouttwelve carbon atoms per alkenyl radical, with said intermediate product,in a molar proportion of about 2:1, respectively, at a temperature ofbetween about 110 C. and about 130 C.

13. The final reaction product obtained by initially reacting a fattyacid containing at least about five carbon atoms per molecule with adialkanolamine having between two and seven carbon atoms per alkanolradical, in a molar proportion of about 1:1, respectively, at atemperature of between about 130 C. and about 160 C. to produce anintermediate product, and then reacting an alkenyl succinic acidanhydride with said intermediate product, in a molar proportion ofbetween about 1:1, respectively, and about 2:1, respectively, at atemperature of between about 110 C. and about 130 C.

14. The reaction product of claim 13, wherein said fatty acid containsbetween about 8 and about 30 carbon atoms per molecule.

15. The reaction product of claim 14, wherein said dialkanolamine is acompound having the formula, HN(CH2CHROH)2, wherein R is selected fromthe group consisting of hydrogen atoms and alkyl radicals.

16. The reaction product of claim 15, wherein said fatty acid is stearicacid.

1'7. The reaction product of claim 15, wherein said fatty acid is oleicacid.

18. The final reaction product obtained by initially reacting stearicacid with diethanolamine, in a molar proportion of about 1:1,respectively, at a temperature of between about 130 C. and about 160 C.to produce a reaction product, and then reacting an alkenyl sucoinicacid anhydride, having between about ten and about twelve car bon atomsper alkenyl radical, with said intermediate product, in a molarproportion of about 2:1, respectively, at a temperature of between about110 C. and about 130 C.

19. The final reaction product obtained by initially reacting stearicacid with diethanolamine, in a molar proportion of about 1:1,respectively, at a temperature of between about 130 C. and about 160 C.to produce an intermediate product, and then reacting an alkenylsuccinic acid anhydride, having between about eight and about ten carbonatoms per alkenyl radical, with said intermediate product, in a molarproportion of about 2:1, respectively, at a temperature of between about110 C. and about 130 C.

20. The final reaction product obtained by in- 19' itially reacting olic"acid with idiethan'olamine, in a molar proportion of about 1:1,respectively; at a, temperature .of between about 130. C. and

about 160 C; 'to produce an intermediate product, and. then reacting analkenyl succinic acid ,an-

HENRY D. NQRRIS.

Number ase- 49 References time the "me 1653 'fiiif'bitfii" f UNITEDSTATES PA ENTS Name Wayne Dec. 17 1940 Robinson et a1 Apr.4, 1944 BlairDec. 17,1946 Barber et a1. Oct. 11, 1949 Trigg et a1 Dec. (#1949

1. A CORROSION-INHIBITING COMPOSITION WHICH COMPRISES A SUBSTANTIALLY NEUTRAL VEHICLE CONTAINING BETWEEN ABOUT 0.01 PER CENT AND ABOUT 50 PER CENT, BY WEIGHT, OF THE FINAL REACTION PRODUCT OBTAINED BY INITIALLY REACTING A FATTY ACID CONTAINING AT LEAST ABOUT FIVE CARBON ATOMS PER MOLECULE WITH A DIALKANOLAMINE HAVING BETWEEN TWO AND SEVEN CARBON ATOMS PER ALKANOL RADICAL, IN A MOLAR PROPORTION OF ABOUT 1:1, RESPECTIVELY, AT A TEMPERATURE OF BETWEEN ABOUT 130* C. AND ABOUT 160* C. TO PRODUCE AN INTERMEDIATE PRODUCT, AND THEN REACTING AN ALKENYL SUCCINIC ACID ANHYDRIDE WITH SAID INTERMEIDATE PRODUCT, IN A MOLAR PROPORTION VARYING BETWEEN ABOUT 1:1, RESPECTIVELY, AND ABOUT 2:1, RESPECTIVELY, AT A TEMPERATURE OF BETWEEN ABOUT 110* C. AND ABOUT 130* C. 